Abstract Dietary vegetables and fruit may play a significant role in atherosclerosis. We investigated the effects of a high intake of vegetables, berries, and citrus fruit along with a diet low in total and saturated fat on plasma concentrations of lipids, lipoprotein(a), antioxidants, oxidised LDL (OxLDL), folate, homocysteine, and on serum paraoxonase-1 activity. We also determined whether gene polymorphisms affect diet response of plasma homocysteine and serum paraoxonase-1 activity. Thirty-seven healthy females consumed two diets (low and high vegetable diets) in a controlled crossover intervention. The plasma measurements were determined at the baseline and at the end of diet periods. The average plasma concentrations of total, LDL, and HDL cholesterol were 5.0 mmol/l, 2.8 mmol/l, and 1.7 mmol/l, respectively, on the low vegetable diet, and decreased by 8%, 8%,and 5%, respectively, in response to the high vegetable diet. The high vegetable diet increased the plasma concentrations of alpha-carotene, beta-carotene, lutein-zeaxanthin, beta-cryptoxanthin, and vitamin C by 133%, 134%, 107%, 65%, and 25%, respectively, compared with the low vegetable diet. There were no differences in the plasma concentrations of OxLDL between the low and high vegetable diets. The mean serum paraoxonase-1 activity was lower at the end of the high vegetable diet (226 U/l) than at the end of the low vegetable diet (240 U/l). Subjects having a genotype with high baseline paraoxonase-1 activity showed the most extensive reduction in their serum enzyme activities. The high vegetable diet enhanced the serum and erythrocyte folate concentrations by 78% and 14%, respectively, and reduced the plasma homocysteine by 13% compared with the low vegetable diet. The dietary treatment was effective even among subjects homozygous for C677T mutation in methylenetetrahydrofolate reductase gene, who are susceptible to high homocysteine levels. In conclusion, a high intake of vegetables, berries, and citrus fruit resulted in reduced plasma total and LDL cholesterol concentrations and enhanced plasma antioxidant levels. The high vegetable diet also effectively increased blood folate concentrations and reduced plasma homocysteine concentration.

Abstract The incidence of pre-eclampsia (PE) is 2–7% in different populations and in the worst cases PE may threaten the survival of both mother and newborn; its pathogenesis is not resolved. Field literature today considers PE an angiogenic disorder. Coordinated vascularization is essential for placental development. We wanted to find novel factors in the etiology of PE, and focused our attention on angiogenesis, inherited thrombophilia and folate-homocysteine metabolism. Homocysteine inhibits endothelial cell proliferation, which is closely related to angiogenesis. We performed gene expression profiling of placental tissue using microarray chips, studied the prevalence of factor V Leiden (FVL), prothrombin (F5) G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in patients with severe pregnancy complications and normal controls, compared the expression of the placental adiponectin, leptin and their receptor genes and the relationship of each to trophoblast apoptosis and further, studied the effect of folic acid fortified mineral water on plasma homocysteine concentration during pregnancy. Gene expression profiling revealed downregulation of nine and upregulation of four genes. Interestingly, in one PE patient with cord compression during delivery the profile resembled that observed in normals. The expression level of the leptin and the adiponectin receptor 1 (ADIPOR1) genes was significantly higher in PE. No other significant expression changes were observed. The rate of apoptosis was higher in patients with PE. The FVL prevalence was 9.5%, in PE cases and 1.8% in the controls; a difference of 7.7%, (95% CI 2.0–13.4%). No statistical difference was found in other polymorphisms.. Maternal serum folate concentration increased in our intervention group, but decreased in the control group (p < 0.05). The plasma homocysteine concentrations decreased more in the intervention group (p < 0.001). The expression of angiogenesis-related placental genes can be altered in PE and cord compression cases. The activity of adipocytokine genes in PE may mean that they have a role in placental angiogenesis and apoptosis. Women with FVL may have an increased risk of PE. Fortified mineral water will help us to ensure that especially pregnant women achieve adequate folate intake.

Orientadores: Nelci Fenalti Höehr, Joyce Maria Annichino-Bizzacchi / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T12:13:12Z (GMT). No. of bitstreams: 1 Barnabe_Aline_D.pdf: 1712567 bytes, checksum: 647e2ea59dbddb21e153a8e6ceae61cc (MD5) Previous issue date: 2014 / Resumo: Folato, vitamina B12 e ferro são nutrientes essenciais, cujas deficiências afetam indivíduos em todas as faixas etárias, sendo consideradas um problema de Saúde Pública no mundo. Níveis reduzidos de folato e vitamina B12 podem estar associados com níveis elevados de homocisteína (Hcy), e que eventualmente resultam em complicações. Entretanto, no Brasil, poucos estudos avaliaram a prevalência dessas deficiências, principalmente de folato e vitamina B12, após a fortificação de farinhas com ácido fólico e ferro. Os objetivos do presente estudo foram: avaliar a prevalência das deficiências de folato, vitamina B12 e ferro em idosos, crianças, gestantes e lactantes após a fortificação de farinhas com ácido fólico e ferro adotado pela ANVISA em 2004; e investigar a contribuição de polimorfismos genéticos sobre os níveis de folato, vitamina B12 e Hcy nestes indivíduos. Os indivíduos foram recrutados em Centros de Saúde da cidade de Campinas entre 2006 a 2007. No total, 719 indivíduos incluindo, 262 idosos, 106 crianças, 291 gestantes e 60 lactantes foram incluídos. As concentrações destes nutrientes foram mensuradas por eletroquimioluminescência; a dosagem de Hcy foi realizada por cromatografia líquida de alta eficiência (CLAE); e os polimorfismos foram investigados por PCR-RFLP. Os resultados mostraram que a prevalência das deficiências de folato, vitamina B12 e ferro no grupo total de indivíduos foram de 0,3%, 5,3% e 12,6%, respectivamente. Praticamente não se observou a deficiência de folato, presente apenas em um idoso e uma gestante, enquanto que a deficiência de vitamina B12 foi prevalente em gestantes (8,9%) e idosos (4,2%). Além disso, a deficiência de ferro e anemia ferropriva foram prevalentes em crianças (9,9% e 4,9%, respectivamente), e gestantes (25,1% e 5,5%, respectivamente). A hiperhomocisteinemia esteve presente principalmente em idosos (34,3%). Com relação aos polimorfismos, apenas as gestantes carreadoras dos alelos CT+TT do polimorfismo no gene MTHFR (C677T) mostraram níveis reduzidos de folato (p=0,030). Através da análise múltipla, observamos que os níveis de Hcy foram determinados principalmente pelo folato (p<0,001), vitamina B12 (p<0,001), gênero (p<0,001) e idade (p<0,001) em idosos; vitamina B12 (p= 0,011) em crianças e folato (p=0,002) em gestantes. Nossos resultados demonstraram que na população avaliada, após 2 anos do início da fortificação de farinhas com ácido fólico e ferro, a deficiência de folato é praticamente inexistente, ao contrário da deficiência de ferro e de vitamina B12. A elevada prevalência da deficiência de vitamina B12 em idosos e gestantes deve ser valorizada na prática, devido ao risco de complicações. O mesmo deve ser observado em relação à deficiência de ferro, prevalente em crianças e gestantes. Portanto, medidas como suplementação e a dosagem desses nutrientes, para grupos populacionais de risco, devem ser implementados em políticas de Saúde Pública. Além disso, a hiperhomocisteinemia observada em idosos pode ser um fator de risco ou um marcador de doença arterial, que é comum nesses indivíduos / Abstract: Folate, vitamin B-12 and iron are essential nutrients, whose deficiencies are considerable public health problems worldwide, affecting all age groups. Low levels of folato and vitamin B12 have been associated with high concentrations of homocysteine (Hcy) and can lead to complications. In Brazil, a few studies evaluated the prevalence of these nutrients, especially, folate and vitamin B12, post acid folic and iron fortification era. The aim of this study was to assess folate, vitamin B12 and iron deficiencies in distinct Brazilian populations including elderly, children, pregnant and lactating women, after the initiation of folic acid and iron fortification by Brazilian authorities. We also investigated the contribution of polymorphisms on folate, vitamin B12 and Hcy levels in these individuals. Folate, vitamin B12 and ferritin levels were measured by chemiluminescence immunoassays, and Hcy levels were determined by high-performance liquid chromatography. Genotype analyses of RFC1 A80G, GCPII C1561T and MTHFR C677T polymorphisms were performed by PCR-RFLP. The individuals were recruited from primary care centers in Campinas ¿ Brazil, between 2006 - 2007. In total 719 individuals, including elderly (262), children (106), pregnant women (291) and lactating women (60) were included. The overall prevalence of low folate, vitamin B-12 and iron status was 0.3%, 5.3% and 12.6%, respectively. Folate deficiency was practically inexistent and was observed only in elderly (n=1) and pregnant women (n=1), whereas vitamin B12 deficiency was frequent in pregnant women (8.9%) and elderly (4.2%). Moreover, iron deficiency and iron deficiency anemia were prevalent in children (9.9% and 4.9%, respectively) and pregnant women (25.1% and 5.5%, respectively). Plasma Hcy concentrations were significantly higher in the elderly (34.3%). Pregnant women carrying the MTHFR 677T allele (CT+TT) showed lower serum folate levels (p=0.030), but none of the polymorphisms investigated in this study affected folate, vitamin B12 and Hcy levels in elderly, children and lactating women. After a multivariate analysis, Hcy levels were predicted by variables such as folate (p<0.001), vitamin B12 (p<0.001), gender (p<0.001) and age (p<0.001) in elderly; vitamin B12 (p= 0.011) in children; and folate (p = 0.002) in pregnant women. Our results demonstrated that folate deficiency is practically inexistent in this population, two years after the initiation of folic acid fortification, in contrast to vitamin B12 and iron deficiency. The high prevalence of vitamin B12 deficiency in elderly and pregnant women is relevant due to health complications. Supplementation and measure of nutrients in some groups of the population should be indicated by Public Health¿s policies. Furthermore, hiperhomocysteinemia in elderly can be a risk factor or a marker of arterial disease, which is common in these individuals / Doutorado / Ciencias Biomedicas / Doutora em Ciências Médicas

Alzheimer's disease (AD) is the most common form of dementia, afflicting almost 5 million patients in the US, and impacting millions more, financially, physically and emotionally. Coming in as the 6th leading cause of death in the US, and showing no signs of slowing its annually increasing rates, the world is in desperate need of improved understanding of the disease's multifaceted pathogenesis and progression, more accurate forms of detection and diagnosis, and more effective prevention and treatment. While many are focused on the noble pursuit of understanding the genetic contributions to the appearance of the pathological amyloid beta (Aβ)) plaques and tau tangles seen in AD, the majority of cases are not explained by genes or allele risk. Instead environmental, dietary and lifestyle contributors may be the key to understanding, diagnosing and treating this awful disease. Diet especially may impact the body's ability to regulate oxidative stress, which will cause damage within the cell and lead to further dysregulation of iron storage and metabolism. Iron storage is heavily monitored through cellular mechanisms, and the way in which the body reacts involves creation of the Aβ plaques and tau tangles as receptacles for the molecule it has deemed as the cause of the problem, iron. We have aptly named our theory, the Iron Hypothesis, and in the following document will outline the evidence for this hypothesis, and the experiments designed and performed to prove it.First, we aimed to examine the impacts that various treatments would have on a transgenic in-vivo model, examining the cohorts' behavior over several time points. We report a significant difference in the behavioral measures of time, distance, errors and failed trials in the radial arm maze existed between genotype, treatment and sex of the mice. Tissue of the experimental mice was collected, but will be processed and analyzed at a later date.Secondly, we aimed to examine the same cohorts of the in-vivo mouse model for minute anatomical changes that took place over the course of the aforementioned behavioral trials using novel MRI scanning sequences sensitive to the low levels of iron build up. We report significant differences in the UTE scan measures for our western diet treatment at TE's of 1.2ms. Additionally, further investigation and optimization of the protocol may be required to further expand the findings.

Homocysteine is a natural occurring aminothiol. It is an intermediate product in the metabolism of methionine. Methionine is an essential amino acid required for protein synthesis. Metabolic irregularities disrupt homocysteine levels in plasma. Elevated homocysteine levels are directly linked to folate and cobalamin (vitamin B12) deficiencies, and are an independent risk factor for cardiovascular diseases. High homocysteine levels have also been associated with Alzheimer's, osteoporosis, renal failure, cancer, birth defects and pregnancy complications. The association of elevated homocysteine levels with cardiovascular disease and other diseases has generated great interest in the detection of homocysteine. An optical method for the detection of homocysteine has been developed using fluorescein mono- and dialdehydes. Selectivity for homocysteine was achieved based on the characteristic differences between 5- and 6-membered ring heterocyclic amines formed upon the reaction with fluorescein mono- and dialdehydes. 6-membered ring homocysteine-derived thiazinane-4-carboxylic acids were found to be more basic than 5-membered cysteine-derived thiazolidine-4-carboxylic acids. Fluorescence enhancement in response to homocysteine was thus attained by tuning pH and excitation wavelengths. Furthermore, the design and synthesis of a more sensitive fluorophore, fluorescein tri aldehyde has been accomplished based on the aforementioned findings to enable the detection of homocysteine at physiological levels. Calculations of Mulliken charges revealed that the formation of thiazinanes results in modulation of the electron density on the fluorophore leading to higher fluorescence.

No description available.

Introduction: This study aimed to examine the association of smoking status with homocysteine levels and to determine whether the association is modified by oestradiol or cholesterol. Methods: Data (N = 4580) were obtained from National Health and Nutrition Examination Survey 2003–2004 with analysis done in 2018 on adults aged ≥20 years. The outcome was homocysteine; smoking status was the exposure variable and categorized as current, former or never smoker. Generalized linear models were used to examine the associations between smoking status and homocysteine levels, while assessing the impact of oestradiol and cholesterol. Results: After adjusting for age, sex, ethnicity, education and income level, homocysteine levels did differ by smoking status ((current smokers versus never smokers: β: 0.18 CI: 0.00, 0.36), (former smokers: β: 0.10 CI: –0.09, 0.28)). The addition of oestradiol as an interaction term in adjusted models was associated with a 16.6% increase in homocysteine levels when compared to models without the interaction term. Oestradiol but not cholesterol did moderate the association between smoking status and homocysteine levels. Discussion and conclusions: Homocysteine levels did differ across smoking status after adjusting for confounders. Oestradiol did moderate the relationship between homocysteine and smoking status.

Homocysteine (Hcy) has been identified as a primary risk factor for atherosclerosis as it induces endothelial cell (EC) activation/dysfunction and thus potentially initiating atherosclerotic plaque formation. There is accumulating evidence indicating a key role for oxidative stress in mediating Hcy atherogenic effects. The aim of this study was to evaluate the effects of chronic treatment with Hcy on EC activation and to explore the role of oxidative stress in these effects. Human umbilical vein endothelial cells (HUVEC) were cultured and treated chronically with DL-Hcy for 5-9 days. An in vitro flow system was also used to characterize the different types of interactions between DL-Hcy-treated HUVEC and neutrophils under physiological flow conditions. EC activation was studied by characterizing the activation of the JNK pathway and the up-regulation of different cell adhesion molecules (CAM) and cytokines, using different techniques including western blot, immunohistochemical staining, enzyme-linked immunosorbent assay and polymerase chain reaction. The role of oxidative stress was investigated by measuring the production of ROS and evaluating the efficiency of antioxidants. Furthermore, the role of nitric oxide and nitric oxide synthase in modulating Hcy effects was investigated. Chronic treatment with DL-Hcy did not kill the EC however, it inhibited cell proliferation. Furthermore, this treatment induced EC activation/dysfunction which was characterized by sustained activation of the JNK pathway, which in turn mediated up-regulation of E-selectin, ICAM-1 and to lesser extent P-selectin. Furthermore, DL-Hcy induced production of IL-8 protein. These CAM and chemokines collectively mediated different interactions between DL-Hcy-treated HUVEC and neutrophils under flow conditions including tethering, rolling, adherence and transmigration. DL-Hcy was also shown to induce significant ROS generation which mediated activation of the JNK pathway. Antioxidants restored DL-Hcy-induced interactions under flow to the basal level. DL-Hcy was shown to induce eNOS uncoupling which mediated, at least in part, the DL-Hcy-induced ROS production. Furthermore, short term treatment with NO inhibited DL-Hcy-induced HUVEC:neutrophil interactions in a cGMP-independent manner. In summary, this research showed that DL-Hcy has several proatherogenic effects, mediated at least in part by the JNK pathway, and induces EC activation/dysfunction priming for atherosclerosis initiation. The data supports that oxidative stress mediates the majority of Hcy atherosclerotic effects. Antioxidants tested, JNK inhibitors and NO showed promising results in reversing all DL-Hcy effects and restoring EC normal status. ¿

10,291 participants, aged 20 to 85 years of age, available from the 1999 through 2002 NHANES databases participated in this study. Only 8,485 (82%) of these participants were included in the data analysis. Participants who were pregnant (n = 603), not examined at a mobile examination center (n = 820), or had missing values for height (n = 164) and/or weight (n = 125) were eliminated. Individuals were classified into four groups (underweight, normal, overweight and obese) based on body mass index (BMI). Variables measured in the study included body mass index, physical fitness, dietary folic acid, c-reactive protein, homocysteine, folate, serum total cholesterol, serum triglycerides, HDL-C, and glucose. All data was collected at Mobile Examination Centers (MEC). The results of the present study showed that being overweight and obese were associated with a poor serum lipid profile, higher serum glucose levels, lower participation in physical activity and a lower physical fitness level. Being overweight and obese was also associated with higher serum levels of inflammatory markers for cardiovascular disease (CVD). Overweight and obese individuals are also being diagnosed with coronary heart disease (CHD) at a younger age.

Cardiovascular disease (CVD) is the leading cause of death worldwide, and is projected to remain so for at least the next decade. Ever since its discovery in the urine and blood of children with inborn errors of metabolism, homocysteine (Hcy) at elevated plasma concentrations has been associated with CVD clinically and epidemiologically. Observational studies and meta-analyses have noted that changes in plasma Hcy by 5&mu;M increase the odds ratio of developing coronary artery disease by 1.6-1.8 among other CVD. Clinical trials aimed at reducing plasma Hcy for benefit against development of subsequent cardiovascular events have had unconvincing results, but have moreover failed to address the mechanisms by which Hcy contributes to CVD. Recommendations from national agencies like the American Heart Association and the United States Preventive Services Task Force emphasize primordial prevention as a way to combat CVD. Reducing plasma Hcy as secondary and primary interventions does not fulfill this recommendation. In order to best understand the role of Hcy in CVD, an investigation into its mechanisms of action must be undertaken before measures of primordial prevention can be devised. Numerous experimental studies in the literature identify vascular endothelium as a target for the pathological effects of Hcy. Endothelial injury and impairment are contributory processes to atherosclerosis, and Hcy has been demonstrated to inhibit endothelial cell (EC) growth and proliferation through mechanisms involving cell cycle arrest, oxidative stress, and programmed cell death in vitro. Animal models have also confirmed that high levels of Hcy accelerate atherosclerotic plaque development and lead to impairment of vascular reendothelialization following injury. Hcy has been shown to have the opposite effect in vascular smooth muscle cells (SMC), causing their proliferation and again contributing to atherosclerosis. The cell-type specificity of Hcy remains to be understood, and among the aims of this research was to further characterize the effects of Hcy in EC. The overarching goal was discovery in order to direct future investigations of Hcy-mediated pathology. To begin, the first investigation considered the transcriptional and regulatory milieu in EC following exposure to Hcy. High-throughput screening using microarrays determined the effect of Hcy on 26,890 mRNA and 1,801 miRNA. Two different in vitro models of hyperhomocysteinemia (HHcy) were considered in this analysis. The first used a high dose of 500µ Hcy to mimic plasma concentrations of patients wherein the transsulfuration pathway of Hcy metabolism is impaired as in inborn cystathionine-ß-synthase deficiency. The other set of conditions used 50µ Hcy in the presence of adenosine to approximate impairment of the remethylation pathway of Hcy metabolism wherein s-adenosylhomocysteine accumulates, thus inhibiting s-adenosylmethionine formation and methylation reactions. These distinctions are important because most clinical trials do not distinguish between causes of HHcy, thereby ignoring the specific derangements underlying HHcy. mRNA and miRNA expression changes for both sets of treatment conditions identified CVD as a common network of Hcy-mediated pathology in EC. Moreover, methylation-specific conditions identified cell cycle modulation as a major contributory mechanism for this pathology, which agrees with recent findings in the literature. Analysis of significant mRNA changes and significant miRNA changes independently identified roles for Hcy in CVD and cell cycle regulation, thereby suggesting that miRNA may mediate the effects of Hcy in addition to gene expression changes alone. To investigate the role of Hcy in the cell cycle further, the next set of investigations considered the effect of Hcy under conditions approximating impaired remethylation in early cell cycle events. Previous studies have demonstrated that Hcy inhibits cyclin A transcription in EC via demethylation of its promoter. Conversely, Hcy induces cyclin A expression in SMC, again making the case for a cell type-specific mechanism in EC. Preceding cyclin A transcription and activation, canonical events in the early cell cycle include D-type cyclin activation, retinoblastoma protein (pRB) phosphorylation, and transcription factor E2F1 activation. In a series of in vitro experiments on EC, it was seen that Hcy inhibits expression of cyclin D2 and cyclin D3, but not cyclin D1. Next, pRB phosphorylation was seen to be decreased following treatment with Hcy. This also led to decreased E2F1 expression. However, this series of events could be reversed with E2F1 supplementation, allowing the cell cycle to proceed. As Hcy exerts a number of its effects via regulation of gene transcription, a final series of investigations aimed to predict potential targets of Hcy by examining patterns of transcription factor binding among known targets of Hcy regulation. Gene promoters of Hcy-modulated genes were analyzed in order to determine common transcription factors that potentially control their regulation. The locations of CpG-rich regions in promoters were identified to determine which regions would be most susceptible to regulation by DNA methylation. Next, high-throughput next-generation sequencing (NGS) and bisulfite NGS was performed for DNA from EC treated with Hcy in order to determine methylation changes after Hcy treatment. A number of potential transcription factors and their binding sites were identified as potential mediators of Hcy-mediated gene regulation. Taken together, these investigations represent an exploration of Hcy-mediated pathology in CVD, by focusing upon novel regulatory mechanisms in EC. Objective high-throughput arrays identified roles for Hcy in CVD and cell cycle pathways regulated by miRNA and gene expression, which were confirmed experimentally in vitro. These observations led to an investigation and identification of common transcription factors that potentially regulate Hcy-altered gene expression. This framework may be used to guide future investigations into the complex pathological network mediating the effects of Hcy in CVD. First, identification of a role for miRNA in mediating the effects of Hcy represents a novel regulatory mechanism, heretofore largely unexplored. Next, expanding the role of Hcy in EC cell cycle regulation to identify upstream mediators greatly adds to the published literature. Finally, noting that these changes center upon transcriptional and post-transcriptional regulation gives import to developing methods to characterize promoter and transcription factor regulation. The investigations presented herein and their results provide evidence that the future of Hcy research is vibrant, relevant, and not nearly surfeit. / Pharmacology